Ivo Karlovic pounded 11 aces Tuesday and knocked off second-seeded Dominik Hrbaty 7-6 (5), 5-7, 6-4 in the first round of the St. Petersburg Open. Hrbaty, ranked 14th and looking for his fourth title this season, converted all three of his break points in the second set to level the match, but the 62nd-ranked Karlovic took the final set.